wen
Harmless cyst, usually on the scalp or face, containing the fatty
secretion of a sebaceous gland.

whortleberry
Two deciduous shrubs, Vaccinium myrtillus, of Eurasia, or V. corymbosum,
of eastern North America, having edible blackish berries.

wontedness
Being accustomed.

yarrow
Plants of the genus Achillea, especially A. millefolium, native to
Eurasia. Also called achillea, milfoil.

yellow fever (yellow jack)
Infectious tropical disease caused by an arbovirus transmitted by
mosquitoes of the genera Aedes, especially A. aegypti, and Haemagogus;
it causes high fever, jaundice, and gastrointestinal hemorrhaging.

yerba reuma
A low California undershrub (Frankenia grandifolia).

Zingiber
Tropical Asiatic and Polynesian perennial plants: ginger.

zwieback
Sweetened bread baked as a loaf and then sliced and toasted.